Improvement in pianos



dotted' (States @anni @wie Letters Patent No. 99,655, dated February 8,1870.

IMPROVEMENT IN PIANOS.

The Schedule referred to in these Letters Patent and making part of the'same.

in Pianos; and I do hereby declare the following to he a full andcorrect description of the same, suiiicient to ena'ble others skilled inthe art to which my invention appertains, to fully understand and usethe same,

reference being had to the accompanying drawings,

which make part of this specification, and in which- Figure l is aperspective view of my improvement in pianos, and

Figures 2 and 3 are partly-sectional detached views of parts ofthe same.

Like letters of reference indicate like parts in the several figures. i

The nature of my invention consists in the manner of tuning, and keepingin tune, the strings of a piano, by means of separate tuning-pins, andin the manner ot'fasteningthe strings. l

A, in the-drawings, mayrepresent the metal frame of a piano, onI thewooden frame B.

C is the sounding-board, on which the bridge D is secured.

At the end A', of the frame A, are secured lthe inclined pins a, aroundwhich the strings c pass, their free ends passing through holes in pinsb, in part A" of frame A, aroundv which they are coiled in tighteningthe strings.

These pins b, as usually constructed, are entirely smooth, and thickerat one end than at the other, and pass thro'ugh the metal frime into thewood, in which theyare held by friction, the holes in the metai frame,through which they pass, being larger than the pins, to allow them topass freely. In pianos provided with these pins, the wood-in which theirlower ends are heldfrequently shrinks by the temperature, thus looseningthe pin, which thus is allowed to move, if only a very little, in themetal hole, and this is'a common and frequent cause of pianos gettingout oftune.

I` construct my pins b with a shoulder, b', below which they end in .astraight screw, which screws firmly into holes d, providedwitlifemale-screw threads, unt-il the shoulder b rests firmly n themetal part A. The strings are 'so apportioned that when the shoulder b'rests on the metal frameA, the string gives a tone a shadow lower thanit is intended to have. 'Ihe tension of the strings is not powerfulenough to turn the pins b, in their holes, and thus uo shrinking of thewood can have any effect on the strings.

To give the stringits proper tone, I use, additional pins e, providedwith a head, c', and a screwend, f. On this pin slides freely a smallblock, g, having, on its. under side, a. groove,` g', which seizes overthe strings c. These pins e are screwed into the metal frame A, betweenpapt A and bridgeE.

As the tone of the string is given by that part of it between thebridges D and E, it will be easily understood that by screwing in pinse, and thus depressing that'part of the string between frame A" andbridge E, by'me'ans of blocks g, the strings between the bridges D and Ewill be tightened, and thus ahigher pitch of tune obtained. A

It will be easily understood that the slightest turn of pins e willexertan influence on the strings c, and that an infinitely finer shade oftuning can be obtained than by turning the pins b.

Having thus described my invention,

`\Vhat I claim as new, and desire to secure by Lettels Patent, is-'- 1.'lhe'tuning-pins e, when operating substantially as and for the purposesset forth.

2. The string-holding pins b, when constructed with a shoulder, b', anda screw-end, in combination with the tuning-pins e, substantially as andfor the purpose set forth.

3. The pins b, when operating and secured in the metal flame Af',without passing into the wood-frame, substantiallyas and for thepurposes set forth.

' ANDREAS F. DESSAU.

vVi/'itnesses ALEXR. A. C. KLAUCKE, J om: P. SUwnnKnoP.

